[H-GEN] Tape Drives

[Robert Brockway]

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On Sun, 6 Jan 2002, Frank Brand wrote:

Hi Frank.

> Ever since hard drives have become reasonable in price it has been my belief
> that removable hard drives are better value than tape decks. $1325 would get
> you 6 extra (maybe 7) hard drives which you could use to back up onto using
> removable drive adapters or USB adapters or whatever. The HDD's are more
> reliable and faster. The tape costs for a drive are not inconsiderable too.

I had a bad experience with removeable HDs.  From what I understand they
were never meant to be pulled in & out often (even if they are hotswapable
- which some are).  I endefd up with partition table failures on numerous
occassions when trying to use a removeable HD as a backup.  I took the HD
out and put it in normally and have had no further problems with it.

Anyway, after this occured I asked around and a few people said they had
had similar experiences.  So I've been turned off from the idea in a big
way :)

Can't comment on how well a usb solution might go.

> Most companies I see (operating on a 5 day week say) might use 5
> tapes....one for each day of the week, or sometimes 10 tapes over a two week
> cycle (some just do incemental back ups for 4 or 9 days and a full backup on
> day 5 or 10 etc). Assuming that 5 tapes are used (if you want to keep your
> backups for a full month maybe 20 or 28 tapes might be needed) that might
> cost $300 or more in tapes. This would buy another 1 or two HDD's or a
> year's supply of CD's. A CD burner is a good backup option too but 40 Gb on
> CDs would be a pain in the bum.

Exactly.  One of the big things to consider is how annoying is full
recovery going to be.  Ultimately, you'd like a full restore to be a case
of:

1.  Boot box from CD of your favourite OS.
2.  Partition hard drive.
3.  Put tape in tape drive.
4.  Issue relevant restore command.
5.  Get coffee because it's 2am (don't catastrophic failures always occur
    in the early hours :)

> Also some tapes are limited to 99 uses IIRC - not sure whether you can clear
> that or not

Some will do even less writes than that.  Another good reason to do a mix
of full & incremental backups (as you mention later in your email).

> Maybe you also need a record for month end, quarter end etc (for accounting
> requirements) but that might be dependent on company policy. In which case,
> keeping them as a permanent copy on CD (or DVD now - there is another
> option, a DVD burner) might be better

It think DVD burners are limited to 4Gb aren't they?  I know Pat is
chasing at least 12Gb raw.

> Maybe other people have different ideas.

Despite their warts, tape is still my preferred backup solution.  The
tapes aren't normally too expensive (cartridges can be), they are small
(normally) so you can put them in your pocket on the way home, and they do
hold alot of data (not as much as a modern HD admittedly).
Cheers,
	-Rob

-- Robert Brockway B.Sc. email: robert at timetraveller.org  ICQ: 104781119
   Linux counter project ID #16440 (http://counter.li.org)
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